The present application may be related to the following commonly owned U.S. patent applications, which are hereby incorporated herein by reference in their entireties:
U.S. patent application Ser. No. 09/846,886 entitled OPTICAL LIMITER BASED ON NONLINEAR REFRACTION, filed on May 1, 2001 in the names of Edward H. Sargent and Lukasz Brzozowski; and
U.S. patent application Ser. No. 09/933,315 entitled OPTICAL LOGIC DEVICES BASED ON STABLE, NON-ABSORBING OPTICAL HARD LIMITERS, filed on even date herewith in the names of Erik V. Johnson and Edward H. Sargent.
The present invention relates generally to optical information processing, and more particularly to storing an optical signal in the optical state.
In today""s information age, optical communication technologies are being used more and more frequently for transmitting information at very high speeds. Traditionally, information processing equipment (such as switches, routers, and computers) process information electronically. Therefore, optical communications are often converted into electronic form for processing by the information processing equipment. This electronic processing is slow relative to the speed of the optical communications themselves, and thus often becomes a xe2x80x9cbottleneckxe2x80x9d of optical communication and processing systems.
Optical information processing systems process information optically without the need to convert the information to an electronic form for processing electronically. One challenge in an optical information processing is the storage of an optical signal. Traditionally, storage of an optical signal would be accomplished by detecting the signal with a photodetector, converting it into excited carriers, and then storing these excited carriers electronically. This technique for storing optical signals is limited by the speed of the electronics and becomes unsatisfactory as optical communication speeds increase.
Thus, optical information processing systems need to store an optical signal in the optical state. The use of bistable devices to store optical signals has been explored (U.S. Pat. Nos. 4,573,767, 4,930,873, 5,349,593, 5,461,507, 5,537,243), and the use of stable devices with feedback has also been examined (U.S. Pat. Nos. 5,617,232, 5,999,284). As well, devices which store information as a chemical reaction have been patented (U.S. Pat. Nos. 4,864,536, 4,992,654, 5,479,384, 6,005,791).
In accordance with one aspect of the invention, an optical sampler based on stable, non-absorbing optical hard limiters includes an optical feedback loop for storing an optical signal in optical form. The optical feedback loop includes appropriate components for amplifying/reproducing the stored optical signal. The optical sampler outputs the stored optical signal.